Esters of sulphonated carboxylic acids



Patented Feb. 25, 1936 ESTERS OF SULPHONATED CARBOXYLIC ACIDS Heinrich Bertsch, Chemnitz, Germany, assignor to the firm H. Th. Biihme Aktiengesellschaft,

Chcmnitz, Germany N0 Drawing. Original application January 29,-

1930, Serial No. 424,456. Divided and this application September 1, 1933, Serial No. 687,913. In Germany February 6, 1929 9 Claims.

This invention relates to the production of compounds suitable for use as wetting agents in the textile, leather, and allied industries, and has for its principal object the provision of a practical and simplified process for the manufacture of esters of the sulpho acids such as may be formed by the sulphonation of glycerine fats, cholestride fats, and the corresponding fatty acids, and also of esters of the aromatic sulpho acids which at the same time are cyclic carboxylic acids or carboxylic acids in the side chain. In my prior United States Patent No. 1,823,815, granted September 15, 1931, I have disclosed a process of this character which consists in first producing the esters of the carboxylic acids with alcohol radicals having a low carbon number (for instance up to cetyl alcohol) and by sulphonating such esters. In the sulphonating step of this process it is found-that in addition to the sulphonation of the esters the alkyl or aryl radical attached to the carboxyl group passes solely or in part to the sulphoxyl group so that the end product consists of esters of the sulpho fatty acids, possibly in admixture'with carboxylic acid esters or with esters in which both the sulphuric acid radical and the carboxyl group are esterified. Y

The present application is a division of my prior application Serial No. 424,456, filed January 29,

1930, directed to alternative processes for obtaining the results set forth in my prior patent hereinbefo're mentioned. Thus one object of the invention disclosed in my prior application is the improvement of the above reaction by the employment of an intensive sulphonating agent, it being found that such a sulphonating agent promotes smoother and generally more satisfactory reaction with the lower carboxylic esters. Such an agent may either comprise a milder sulphonating agent, the action of which has been improved by appropriate additions, or -may comprise a sulphonating agent which of itself acts very energetically. Furthermore, such improving additions may also be made to sulphonating agents which are energetic in themselves. The temperature is preferably maintained below 15 C. whereby saponification of the esters to be sulphonated is avoided or confined to a small amount and the yield is correspondingly improved. Such energetic sulphonating agents may, for instance, comprise fuming sulphuric acid, sulphur trioxide (preferably in vapor form or having high percentage oleum) or-chlorsulphonic acid. Mixtures of concentrated sulphuric acid, or of the sulsulphuric acid or chlorsulphonic acid, these de-' rivatives being usedeither alone or in admixture with other sulphonating agents. By such means products are obtained which, for the greater part, are esterified both in the sulpho group and in the car'boxyl group.

It is a feature of the instant invention that alkyl sulphuric acids or alkyl sulpho chlorides may be reacted directly with the carboxylic acids to produce the corresponding esters of the sulphonated acids, a temperature below 15 C. be-

ing preferably maintained during the reaction. The following examples illustrate the manner in which my invention may be practiced.

Example I 48 kgs. of butyl sulphuric acid are added to 100 kgs. of ricinoleic fatty acid at a temperature below 15 C. Ice is added to the reaction mixture,

solution to which is washed with Glaubers salt remove excess sulphuric acid.

Example II 60 kgs. of i-propyl alcohol are reacted with 98 kgs. concentrated sulphuric acid to form i-propyl sulphuric acid. This product is introduced into 150 kgs. of ricinoleic acid at a temperature below 10 C. while stirring intensively. The preparation is continued as in Example I.

Example 111 52 kgs. of n-amyl-sulphuric acid are added to 100 kgs. of ricinoleic fatty acid at a temperature below 15 C. Ice is added to the reaction mixture, which is washed with Glaubers salt solution to remove excess sulphuric acid.

Example IV 45 kgs. of n-propyl-sulphuric acid are added to 100 kgs. of oleic acid at a temperature below 15 C. Ice is added to the reaction mixture, which is washed with Glaubers salt solution to remove excess sulphuric acid.

Example V 48 kgs. of i-butyl-sulphuric acid are added to 100 kgs. of linoleic acid at a temperature below 15 C. Ice is added to the reaction mixture.

which is washed with Glauber's salt solution to remove excess sulphuric acid.

Example VI I 52 kgs. of i-amyl-sulphuric acid are added to 100 kgs. of linoleic acid at a temperature below 15 C. Ice is added to the reaction mixture, which is washed with Glaubers salt solution to remove excess sulphuric 'acid.

Example VII Q 42 kgs. of ethyl sulphuric acid are added to 100 kgs. of oxystearic acid at a temperature below 15 C. Ice is added to the reaction mixture,

which is washed with Glaubers salt solution to tended to cover reactions which may result either in the formation of true sulphonic acids, sulphuric acid esters, or both, it being understood in the art to which this invention relates that the nature of the resultant product depends largely upon the conditions and the materials which enter into the reaction. Thus the terms sulphonation and sulphonation produc are used generically to describe the reaction and the reaction product resulting from the use of anywell-known sulphating and sulphonating agent.

I prefer generally to employ alkyl sulphuric acids having from 1 to 12 carbon atoms and fatty acidsor fatty acid mixtures which contain double bonds or hydroxyl groups, but it will be understood that no limitation of the scope of the invention is intended by the employment of specific examples for the purpose of illustrating the principles thereof.

Having thus described the invention, what is claimed as newand desired to be secured by Letters Patent is:

aoasu 1. The process of producing esters of sulphonated carboxylic acids, which comprises reacting an alkyl derivative of sulphuric acid with a carboxylic acid having more than 10 carbon atoms at a relatively low temperature, whereby products which are esteriiled in both the sulpho and carboxyl groups are obtained.

2. The process of producing esters of sulphonated carboxylic acids,-. which comprises reacting an alkyl derivative of sulphuric acid with a corboxylic acid having more than 10 carbon atoms at. a temperature less than 15 C.

3. The process of producing esters of sulphonated carboxylic acids, which comprises reacting a monohydroxy alcohol with sulphuric acid to form an alkyl sulphuric acid, and mixing the latter with a carboxylic acid having more than 10 carbon atoms at a relatively low temperature, whereby products which are esterified in both the sulpho and carboxyl groups are obtained.

4. The process of producing esters of sulphonated carboxylic acids, which comprises reacting a monohydroxy alcohol with sulphuric acid to form an alkyl sulphuric acid, and mixing the latter with a carbonylic acid having more than 10 carbon atoms at a-temperature less than 15 C.

5. The process of producing esters of sulphonated carboxylic acids, which comprises reacting an alkyl' sulpho-chloride with a carboxylic acid having more than 1-0 carbon atoms at a relatively low temperature, whereby products which are esterifled in both the sulpho and'carboxyl groups are obtained.

6. The process of producing esters of sulphonated carboxylic acids, which comprises reacting an alkyl derivative of sulphuric acid having not.

more than 12 carbon atoms with a carboxylic acid having more than 10 carbon atoms at a temperature less than 15 C.

'1. The process or producing esters of sulphonated carboxylic acids, which comprises reacting butyl sulphuric acid with ricinoleic fatty acid at a temperature below 15 C.

8. The process of producing esters of sulphonated carboxylic acids, which comprises reacting butyl sulphuric acid chloride with ricinoleic fatty acid at a temperature below 15 C. 1

9. A process which comprises reacting alkyl derivatlves oi sulphuric acid having not more than 12 carbon atoms with fatty acids having more than 10 carbon atoms at a relatively low temperature, whereby products which are esterifled in both the sulpho and carboxyl groups are obtamed.

- HEINRICH BERTSCH. 

